Thursday, December 20, 2012

Anti-fragility

There was a great interview of Nassim Taleb on the BBC Daily Business broadcast that very succinctly summarizes his concept of anti-fragility.  As an industrial engineer, I have always promoted system robustness so seeing a fundamental flaw in it is a great piece of learning.  I find this rewarding for two reasons.  Most importantly, I am a better engineer and consultant as a result.  But also, experts have a notoriously hard time giving up ideas that have been a core part of their world-view so it is great to know I can. 

So what is anti-fragility?  Contrasting it with robustness is the best way to explain.  Systems are made up of many components.  Fragile systems are those where the failure of one of these components causes a failure of the whole system.  So robustness is an approach where you try to make each component resistant to failure.  If you prevent these small failures, you don't get the system-wide failure.  But this is where you get Taleb's Black Swan.  When you get a problem big enough to fail one of your robust components, the whole system fails so completely that it becomes a disaster.  The 2007 banking crisis is the example that made Taleb famous.  We also see it in modern forest fire prevention.  The more we prevent small fires from breaking out, the more disastrous the eventual state-wide wildfires we get.

So anti-fragility takes the opposite approach.  Let's design the system components so that they fail easily, but so that the system as a whole gets better as a result.  Small and frequent forest fires made the whole forest safer.  The more companies that go bankrupt in a country, the less risk there is that the whole economy will crash. 

Here is an example I have been considering in my personal life.  Many new parents are trying to prevent their infants from getting sick in any way.  Don't let them anywhere near a peanut, piece of dirt, germ . . .   But what seems to be happening is that the kids grow up to be more fragile rather than less.  They are more likely to have allergies, asthma, and other immune-system related diseases.  I like the old way better.  Let our kids grow up playing in mud, eating dirt and 15-second rule Cheerios.  I read somewhere that the Chinese have such a low incidence of peanut allergies because their kids start eating boiled peanuts at such a young age they haven't had a chance to develop an allergy yet. Plus, this seems like a less stressful way to live. 

Where else should we anti-fragile rather than robust?